We're going to turn to the stunning arrest of a drug kingpin that goes by the name dread pirate roberts. Appears to have cornered the internet drug market. His real name is ross ulbricht. Gio benitez is here with all of the details. Good morning, gio. Reporter: Good morning to you. The fbi calls it the most sophisticated criminal marketplace on the internet. Thousands of drug dealers used it to sell drugs and completely hide their identities. This morning, the fbi says that 29-year-old seemingly clean-cut entrepreneur was living a secret life as a digital drug lord operating an online black market bazaar, called silk road. Here's an online commercial. Now, ross ulbricht is in federal custody. Arrested tuesday. And the site he allegedly ran, shut down after a two-year undercover operation. A sophisticated individual who took the skills and the talents and developed an online website that marketed illegal goods and services. Reporter: Just look at some of the 13,000 items offered through that underground site. Ultraclean cocaine. Clean and real lsd. High-grade mdma, also known as molly. All with fast and free shipping. Court documents say silk road sold $1.2 billion worth of drugs and illegal services in just under three years. They were comfortable operating in that environment because they felt that they enjoyed complete anonymity. Reporter: Investigators say the penn state graduate tried hiding his identity on silk road with the user name dread pirate roberts. Just like in the movie "the princess bride." You're the bred pirate roberts, admit it. Reporter: It seems one silk road user threatened to reveal the identities of thousands of others. Investigators say ulbricht tried to execute a murder-for-hire on that user, offering $150,000 to a would-be hitman because, quote, this kind of behavior is unforgivable to me, especially here on silk road. Anonymity is sacrosanct. Just because silk road is shut down doesn't mean the concept will go away easily. The operator made $80 million in fees. That's a huge incentive. Reporter:80 million. Ulbricht's attorney, a public defender, has not returned our called for comment. Investigators say his key mistake, he allegedly used his personal e-mail address for nearly all silk road communications, george. Thanks very much. Let's talk to dan abrams about this, our chief legal affairs anchor. I'm amazed that a website like this could stay up for so long. It's accessed through a special network on the internet, which allowed users to immediately encrypts, masks who they are. So, you can't identify what their i.P. Address is. And the payment system is through bitcoin, which is digital currency. Not backed up by international banks. Not backed up by u.S. Banks. But simply based on the confidence of the users who exchange these bitcoins computer to computer. The fbi's case is based on the idea if they can show that dread pirate roberts is ross ulbricht? Can they link -- he was trying to hide his identity on the site, as well. So, the first thing they're going to have to do is definitively link him as the person who runs the site. And typically when you're talking about a website, people would say, if people are exchanging information and they're dealing drugs, it's not our responsibility. We just put up the site. The problem is, in this site, they're taking commissions. And you have a beautiful site. Looks like amazon in the sense that it's got all the different kinds of drugs that are for sale up there. It will be very difficult to claim, we didn't know about what was happening on the site. We heard at the end of the piece, this is not going away. No. This is -- this is going to be the biggest takedown of what is currently in existence. And you're now going to see them on warning. And you're going to see a bunch of smaller entities begin to try to take over.

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